柚子皮衍生的分级多孔碳作为高性能超级电容器的电极材料

摘要

We propose a novel method using cetyltrimethyl ammonium bromide (CTAB) as soft template followed by successive graphitization and activation of pomelo peel to get a new biomass-derived hierarchical porous carbon (HPC).The as-obtained HPC possesses a high specific area of 1 813 m2·g-1 with abundant mesopores structure,which is larger than that of 1 184 m2·g-1 for the contrast of the porous carbon (PC) prepared without CTAB.X-ray photoelectron spectroscopy (XPS) analysis presents the oxygen doped amount for HPC is larger than that for PC,which could arise a high pseudocapacitance.In addition,the HPC also shows better electrochemical performance than PC,when utilized as an electrode material in supercapacitor.At a current density of 0.5 A·g-1,the specific capacitance of HPC is up to 285 F· g-1 in 1 mol ·L-1 KOH solution.Further investigation based on two-electrode cell suggests good performance with high rate capability and relative stability.Such excellent performance should be attributed to the synergistic effect of large specific surface area,high O-doping content and reasonable pore-size distribution.%使用CTAB作为软模板,水热处理柚子皮,再以碳化和KOH活化过程得到了分级多孔碳(HPC),这种分级多孔碳材料的比表面积高达1 813 m2·g-1,相比于没有水热步骤制备的多孔碳(PC),拥有更加丰富的介孔结构和更大的比表面积.XPS分析结果表明HPC的氧掺杂量更高,会比PC贡献更大的赝电容.三电极测试体系中,HPC的比电容达到285 F·g-1(0.5 A·g-1,1 mol·L-1 KOH).同时,组装的两电极对称超级电容器拥有很好的倍率性能,循环12 000次充放电后,比电容依旧保留99％.HPC拥有这样优异的性能归结于较大的比表面积,高氧掺杂量和合理的孔径分布的协同作用.